From the beginning of its membership in NIDA's Clinical Trials Network (CTN) in 2000, the Ohio Valley Node (OVN) has been an effective, enthusiastic, and energetic node that has excelled in providing scientific and administrative leadership, in collaborating with other nodes and with NIDA and contract staff, and in disseminating information about evidence-based practices and the results of CTN studies. The OVN's Community Treatment Programs (CTPs) and its Regional Research and Training Center (RRTC) have worked together to create a node in which the CTN's goal of bilateral communication/collaboration between researchers and treatment providers has been fully realized. The success in integrating all members of this geographically dispersed node into a unified whole, together with the strong commitment of the Node PI, CTP PIs, and RRTC staff to full participation in the CTN, have enabled the OVN to be extremely productive throughout its membership in the CYN. The OVN has an experienced staff, including several RRTC and CTP PIs who have been with the OVN since its formation. The OVN continues to collaborate with a growing number of CTPs which have a variety of patient characteristics and extend over a broad geographical range now encompassing the entire Midwest (12 states) and the Upper-South states of Kentucky, Tennessee, and West Virginia. The 23 OVN CTPs, which together receive more than 100,000 patient visits a year, will contribute significantly to the number and variety of potential participants for CTN studies. The OVN administrative and management plans for the next five years capitalize on the strengths of the OVN: experience, teamwork, and varied areas of expertise (including HIV/AIDS, emergency medicine, integration of addiction treatment into primary care, and telemedicine), so the OVN can continue to contribute scientific leadership and excellence in developing/conducting CTN protocols. The OVN has detailed a research agenda designed to improve opioid dependence treatment by optimizing medication-assisted treatment and expanding office-based opioid treatment. Already cooperating actively with the four Addiction Technology and Transfer Centers (ATTCs) associated with the states covered by the OVN, the Node plans to strengthen relationships with other networks (e.g., Cincinnati Center for Clinical & Translational Science & Training).